Clethra alnifolia is an upright, deciduous flowering shrub growing to 1.5-3 m tall. It is a native to the eastern U.S.This cultivar is called 'Hummingbird', for its dwarf size. The leaves are obovate to oblong, 4-10 cm long and 2-4 cm broad, with a serrated margin; they are green turning yellow-golden during the autumn.Clethra alnifolia bears white, deliciously spicy clove-scented flowers in dense, upright racemes up to 15 cm long and 2 cm broad that last four to six weeks. The flowers are creamy white or very pale pink, 5-10 mm diameter and are attractive to bees and butterflies. Flowers mature to spikes of dark brown capsules and its oval, glossy dark green leaves turn a pleasant yellow in autumn.The "Pepper" part of the common name derives from the mature fruits, capsules which have a vague resemblance to peppercorns, however, with no element of spiciness.